The yen rose past the psychological key level of ¥140 against the dollar, as the Japanese currency extended a rally that began in July after hitting its weakest point in nearly 38 years.
The currency rose as much as 0.6% against the dollar on Monday to ¥139.96, its highest level since July 2023.
The yen was the best-performing Group of 10 currency this quarter, gaining 15% as investors brace for a further narrowing of the interest rate gap between the U.S. and Japan. The Federal Reserve appears all but certain to cut U.S. borrowing costs on Wednesday — the only question is by how much — while the Bank of Japan (BOJ) is expected to leave interest rates unchanged on Friday after raising rates twice this year.